📄 buops.cpp
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/* Copyright (c) 1989 Citadel */
/* All Rights Reserved */
/* #ident "@(#)buops.c 1.4 - 90/06/20" */
/* local headers */
#include "blkio_.h"
/* check host definition */
#ifndef HOST
/*#error HOST macro not defined.*/
#endif
#if HOST != UNIX && HOST != MS_DOS
/*#error Invalid HOST macro definition.*/
#endif
/* ansi headers */
#include <errno.h>
/* system headers */
#if HOST == UNIX /* UNIX */
#include <fcntl.h> /* open() macro definitions */
#include <unistd.h> /* lseek() macro definitions */
#ifdef AC_PROTO
int close(int fd); /* system call declarations */
long lseek(int fd, long offset, int whence);
int open(const char *path, int flags, ...);
int read(int fd, char *buf, unsigned n);
int write(int fd, const char *buf, unsigned n);
#else
int close();
long lseek();
int open();
int read();
int write();
#endif /* #ifdef AC_PROTO */
#define MODE (0666) /* file permissions for new files */
#elif HOST == MS_DOS /* MS-DOS */
#if MSDOSC == TURBOC /* Turbo C */
#include <fcntl.h> /* open() macro definitions */
#include <io.h> /* system call decls, lseek() macro defs */
#define MODE (0x100 | 0x080) /* file permissions for new files */
#elif MSDOSC == MSC /* Microsoft C */
#include <fcntl.h> /* open() macro definitions */
/*#include <io.h> /* system call decls, lseek() macro defs */
/* NOTE: <io.h> not used for MSC because const qualifier missing from
open and write decls */
#ifdef AC_PROTO
int close(int fd); /* system call declarations */
long lseek(int fd, long offset, int whence);
int open(const char *path, int flags, ...);
int read(int fd, char *buf, unsigned n);
int write(int fd, const char *buf, unsigned n);
#else
int close();
long lseek();
int open();
int read();
int write();
#endif /* #ifdef AC_PROTO */
#define MODE (0x100 | 0x080) /* file permissions for new files */
#elif MSDOSC == MSQC /* Microsoft Quick C */
#include <fcntl.h> /* open() macro definitions */
/*#include <io.h> /* system call decls, lseek() macro defs */
/* NOTE: <io.h> not used for MSQC because const qualifier missing from
open and write decls */
#ifdef AC_PROTO
int close(int fd); /* system call declarations */
long lseek(int fd, long offset, int whence);
int open(const char *path, int flags, ...);
int read(int fd, char *buf, unsigned n);
int write(int fd, const char *buf, unsigned n);
#else
int close();
long lseek();
int open();
int read();
int write();
#endif /* #ifdef AC_PROTO */
#define MODE (0x100 | 0x080) /* file permissions for new files */
#endif /* #if MSDOSC == TURBOC */
#endif /* #if HOST == MS_DOS */
/*man---------------------------------------------------------------------------
NAME
b_uclose - unbuffered close block file
SYNOPSIS
#include "blkio_.h"
int b_uclose(bp)
BLKFILE *bp;
DESCRIPTION
The b_uclose function closes the file associated with the BLKFILE
pointer bp.
b_uclose will fail if one or more of the following is true:
[EINVAL] bp is not a valid BLKFILE pointer.
[BENOPEN] bp is not open.
SEE ALSO
b_uopen.
DIAGNOSTICS
Upon successful completion, a value of 0 is returned. Otherwise,
a value of -1 is returned, and errno set to indicate the error.
------------------------------------------------------------------------------*/
int b_uclose(BLKFILE *bp)
{
#ifdef DEBUG
/* validate arguments */
if (!b_valid(bp)) {
BEPRINT;
errno = EINVAL;
return -1;
}
/* check if not open */
if (!(bp->flags & BIOOPEN)) {
BEPRINT;
errno = BENOPEN;
return -1;
}
#endif
/* close file */
#if HOST == UNIX
if (close(bp->fd.ifd) == -1) {
BEPRINT;
return -1;
}
#elif HOST == MS_DOS
if (close(bp->fd.ifd) == -1) {
BEPRINT;
return -1;
}
#endif
errno = 0;
return 0;
}
/*man---------------------------------------------------------------------------
NAME
b_uendblk - unbuffered find end block
SYNOPSIS
#include "blkio_.h"
int b_uendblk(bp, endblkp)
BLKFILE *bp;
bpos_t *endblkp;
DESCRIPTION
The b_uendblk function finds the block number of the first block
past the end of file of the file associated with BLKFILE pointer
bp. This value is returned in the storage location pointed to by
endblkp. Blocks in buffer storage and not yet written to the
file are not counted, so this function should normally be used
when the file is first opened or preceded by a call to bsync.
If the file does not end on a block boundary, the result is the
same as if the partial block (or header) at the end of the file
did not exist.
b_uendblk will fail if one or more of the following is true:
[EINVAL] bp is not a valid BLKFILE pointer.
[BENOPEN] bp is not open.
DIAGNOSTICS
Upon successful completion, a value of 0 is returned. Otherwise,
a value of -1 is returned, and errno set to indicate the error.
------------------------------------------------------------------------------*/
int b_uendblk(BLKFILE *bp, bpos_t *endblkp)
{
#if HOST == UNIX
long pos = 0;
#elif HOST == MS_DOS
long pos = 0;
#endif
#ifdef DEBUG
/* validate arguments */
if (!b_valid(bp)) {
BEPRINT;
errno = EINVAL;
return -1;
}
/* check if not open */
if (!(bp->flags & BIOOPEN)) {
BEPRINT;
errno = BENOPEN;
return -1;
}
#endif
#if HOST == UNIX || HOST == MS_DOS
/* find position of end of file */
pos = lseek(bp->fd.ifd, (long)0, SEEK_END);
if (pos == -1) {
BEPRINT;
return -1;
}
/* check if empty file (or incomplete header) */
if (pos < bp->hdrsize) {
*endblkp = 0;
errno = 0;
return 0;
}
/* find length past end of header */
pos -= bp->hdrsize;
/* set return argument */
*endblkp = (pos / bp->blksize) + 1;
#endif
errno = 0;
return 0;
}
/*man---------------------------------------------------------------------------
NAME
b_ugetf - unbuffered get field from block file
SYNOPSIS
#include "blkio_.h"
int b_ugetf(bp, bn, offset, buf, bufsize)
BLKFILE *bp;
bpos_t bn;
size_t offset;
void *buf;
size_t bufsize;
DESCRIPTION
The b_ugetf function reads bufsize characters from block number
bn of the block file associated with BLKFILE pointer bp into the
buffer pointed to by buf. A value of 0 for bn indicates the file
header. The read starts offset characters from the beginning of
the block. The sum of the offset and the bufsize must not exceed
the header size if bn is equal to zero, or the block size if bn
is not equal to zero.
b_ugetf will fail if one or more of the following is true:
[EINVAL] bp is not a valid BLKFILE pointer.
[EINVAL] buf is NULL.
[EINVAL] bufsize is less than 1.
[BEBOUND] offset + bufsize extends across a block
boundary.
[BEEOF] Block bn is past the end of file.
[BEEOF] End of file encountered within block bn.
[BENOPEN] bp is not open.
SEE ALSO
b_uputf.
DIAGNOSTICS
Upon successful completion, a value of 0 is returned. Otherwise,
a value of -1 is returned, and errno set to indicate the error.
------------------------------------------------------------------------------*/
int b_ugetf(BLKFILE *bp, bpos_t bn, size_t offset, void *buf, size_t bufsize)
{
#if HOST == UNIX
long pos = 0;
int nr = 0;
#elif HOST == MS_DOS
long pos = 0;
int nr = 0;
#endif
#ifdef DEBUG
/* validate arguments */
if (!b_valid(bp) || buf == NULL || bufsize < 1) {
BEPRINT;
errno = EINVAL;
return -1;
}
/* check if not open */
if (!(bp->flags & BIOOPEN)) {
BEPRINT;
errno = BENOPEN;
return -1;
}
/* check if block boundary is crossed */
if (bn == 0) {
if ((offset + bufsize) > bp->hdrsize) {
BEPRINT;
errno = BEBOUND;
return -1;
}
} else {
if ((offset + bufsize) > bp->blksize) {
BEPRINT;
errno = BEBOUND;
return -1;
}
}
#endif
#if HOST == UNIX
/* read from file into buffer */
if (bn == 0) { /* header */
pos = 0;
} else { /* block */
pos = bp->hdrsize + (bn - 1) * bp->blksize;
}
pos += offset;
if (lseek(bp->fd.ifd, pos, SEEK_SET) == -1) {
BEPRINT;
return -1;
}
nr = read(bp->fd.ifd, (char *)buf, (unsigned)bufsize);
if (nr == -1) {
BEPRINT;
return -1;
}
if (nr != bufsize) {
BEPRINT;
errno = BEEOF;
return -1;
}
#elif HOST == MS_DOS
/* read from file into buffer */
if (bn == 0) { /* header */
pos = 0;
} else { /* block */
pos = bp->hdrsize + (bn - 1) * bp->blksize;
}
pos += offset;
if (lseek(bp->fd.ifd, pos, SEEK_SET) == -1) {
BEPRINT;
return -1;
}
nr = read(bp->fd.ifd, buf, (unsigned)bufsize);
if (nr == -1) {
BEPRINT;
return -1;
}
if (nr != bufsize) {
BEPRINT;
errno = BEEOF;
return -1;
}
#endif
errno = 0;
return 0;
}
/*man---------------------------------------------------------------------------
NAME
b_uopen - unbuffered open block file
SYNOPSIS
#include "blkio_.h"
int b_uopen(bp, filename, type)
BLKFILE *bp;
const char *filename;
const char *type;
DESCRIPTION
The b_uopen function opens the physical file associated with the
BLKFILE pointer bp.
b_uopen will fail if one or more of the following is true:
[EINVAL] bp is not a valid BLKFILE pointer.
[EINVAL] filename or type is the NULL pointer.
SEE ALSO
b_uclose.
DIAGNOSTICS
Upon successful completion, a value of 0 is returned. Otherwise,
a value of -1 is returned, and errno set to indicate the error.
------------------------------------------------------------------------------*/
int b_uopen(BLKFILE *bp, const char *filename, const char *type)
{
#if HOST == UNIX
int oflag = 0;
int fd = 0;
#elif HOST == MS_DOS
int oflag = 0;
int fd = 0;
#endif
#ifdef DEBUG
/* validate arguments */
if (!b_valid(bp) || filename == NULL || type == NULL) {
BEPRINT;
errno = EINVAL;
return -1;
}
#endif
/* open file */
#if HOST == UNIX
oflag = 0;
if (strcmp(type, BF_READ) == 0) {
oflag |= O_RDONLY;
} else if (strcmp(type, BF_RDWR) == 0) {
oflag |= O_RDWR;
} else if (strcmp(type, BF_CREATE) == 0) {
oflag |= O_RDWR | O_CREAT | O_EXCL;
} else if (strcmp(type, BF_CRTR) == 0) {
oflag |= O_RDWR | O_CREAT | O_TRUNC;
} else {
errno = EINVAL;
return -1;
}
fd = open(filename, oflag, MODE);
if (fd == -1) {
if ((errno != EACCES) && (errno != EEXIST) && (errno != ENOENT)) BEPRINT;
return -1;
}
bp->fd.ifd = fd;
#elif HOST == MS_DOS
oflag = O_BINARY;
if (strcmp(type, BF_READ) == 0) {
oflag |= O_RDONLY;
} else if (strcmp(type, BF_RDWR) == 0) {
oflag |= O_RDWR;
} else if (strcmp(type, BF_CREATE) == 0) {
oflag |= O_RDWR | O_CREAT | O_EXCL;
} else if (strcmp(type, BF_CRTR) == 0) {
oflag |= O_RDWR | O_CREAT | O_TRUNC;
} else {
errno = EINVAL;
return -1;
}
fd = open(filename, oflag, (unsigned)MODE);
if (fd == -1) {
if ((errno != EACCES) && (errno != EEXIST) && (errno != ENOENT)) BEPRINT;
return -1;
}
bp->fd.ifd = fd;
#endif
errno = 0;
return 0;
}
/*man---------------------------------------------------------------------------
NAME
b_uputf - unbuffered put field to block file
SYNOPSIS
#include "blkio_.h"
int b_uputf(bp, bn, offset, buf, bufsize)
BLKFILE *bp;
bpos_t bn;
size_t offset;
const void *buf;
size_t bufsize;
DESCRIPTION
The b_uputf function writes bufsize characters from the buffer
pointed to by buf to block number bn of the block file associated
with BLKFILE pointer bp. A value of zero for bn indicates the
file header. The write starts offset characters from the
beginning of the block. The sum of offset bufsize must not
exceed the header size if bn is equal to zero, or the block size
if bn is not equal to zero.
b_uputf will fail if one or more of the following is true:
[EINVAL] bp is not a valid BLKFILE pointer.
[EINVAL] buf is the NULL pointer.
[EINVAL] bufsize is less than 1.
[BEBOUND] offset + bufsize extends beyond the block
boundary.
[BEEOF] Partial block being written and block bn
is past the end of file.
[BEEOF] Complete block being written and block bn
is more than 1 past the end of file.
[BENOPEN] bp is not open for writing.
SEE ALSO
b_ugetf.
DIAGNOSTICS
Upon successful completion, a value of 0 is returned. Otherwise,
a value of -1 is returned, and errno set to indicate the error.
------------------------------------------------------------------------------*/
int b_uputf(BLKFILE *bp, bpos_t bn, size_t offset, const void *buf, size_t bufsize)
{
#if HOST == UNIX
long pos = 0;
int nw = 0;
#elif HOST == MS_DOS
long pos = 0;
int nw = 0;
#endif
#ifdef DEBUG
/* validate arguments */
if (!b_valid(bp) || buf == NULL || bufsize < 1) {
BEPRINT;
errno = EINVAL;
return -1;
}
/* check if not open */
if (!(bp->flags & BIOWRITE)) {
BEPRINT;
errno = BENOPEN;
return -1;
}
/* check if block boundary is crossed */
if (bn == 0) {
if ((offset + bufsize) > bp->hdrsize) {
BEPRINT;
errno = BEBOUND;
return -1;
}
} else {
if ((offset + bufsize) > bp->blksize) {
BEPRINT;
errno = BEBOUND;
return -1;
}
}
#endif
#if HOST == UNIX || HOST == MS_DOS
/* write buffer to file */
if (bn == 0) { /* header */
pos = 0;
} else { /* block */
pos = bp->hdrsize + (bn - 1) * bp->blksize;
}
pos += offset;
if (lseek(bp->fd.ifd, pos, SEEK_SET) == -1) {
BEPRINT;
return -1;
}
nw = write(bp->fd.ifd, (char *)buf, (unsigned)bufsize);
if (nw == -1) {
BEPRINT;
return -1;
}
if (nw != bufsize) {
BEPRINT;
/* call write again to set errno (EFBIG or ENOSPC) */
nw = write(bp->fd.ifd, (char *)buf, (unsigned)1);
if (nw != -1) errno = BEPANIC;
return -1;
}
#elif HOST == MS_DOS
/* write buffer to file */
if (bn == 0) { /* header */
pos = 0;
} else { /* block */
pos = bp->hdrsize + (bn - 1) * bp->blksize;
}
pos += offset;
if (lseek(bp->fd.ifd, pos, SEEK_SET) == -1) {
BEPRINT;
return -1;
}
nw = write(bp->fd.ifd, buf, (unsigned)bufsize);
if (nw == -1) {
BEPRINT;
return -1;
}
if (nw != bufsize) {
BEPRINT;
errno = BEPANIC;
return -1;
}
#endif
errno = 0;
return 0;
}
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